Virtual private local area network service (VPLS) is a point-to-multipoint service, which emulates local area network (LAN) functionality over provider networks. VPLS is described, for example, by Augustyn and Serbest in Internet Engineering Task Force (IETF) Request for Comments (RFC) 4665, entitled “Service Requirements for Layer 2 Provider-Provisioned Virtual Private Networks,” RFC 4665, 2006-09; by Lasserre and Kompella in “Virtual Private LAN Services Using LDP,” IETF Internet draft, 2006-06; and by Kompella and Pekhter in “Virtual Private LAN Service (VPLS) Using BGP for Auto-discovery and Signaling,” IETF Internet draft, 2006-06, which are incorporated herein by reference.
Link aggregation (LAG) is a technique by which a group of parallel physical links between two endpoints in a data network can be joined together into a single logical link (referred to as a “LAG group”). Traffic transmitted between the endpoints is distributed among the physical links in a manner that is transparent to the clients that send and receive the traffic. For Ethernet™ networks, link aggregation is defined by Clause 43 of IEEE Standard 802.3, Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications (2002 Edition), which is incorporated herein by reference.